Wednesday, February 4, 2015

Pinker on insults to the sacred dogma

It is only by bruiting ideas and seeing which ones withstand attempts to refute them that we acquire knowledge.

Once this realization sank in during the Scientific Revolution and the Enlightenment, the traditional understanding of the world was upended. Everyone knows that the discovery that the Earth revolves around the sun rather than vice-versa had to overcome fierce resistance from ecclesiastical authority. But the Copernican revolution was just the first event in a cataclysm that would make our current understanding of the world unrecognizable to our ancestors. Everything we know about the world — the age of our civilization, species, planet, and universe; the stuff we’re made of; the laws that govern matter and energy; the workings of the body and brain — came as insults to the sacred dogma of the day. We now know that the beloved convictions of every time and culture may be decisively falsified, doubtless including some we hold today.

I am all in favor of free speech and the scientific method, but what is he talking about here?

No, almost everything we know about the world was fairly rapidly accepted without much controversy. His first example is the "age of our civilization". By this, I assume he means recorded history that goes back to ancient Babylonians and Egyptians. Was there ever some significant controversy about that age?

The age of the Earth was of some controversy in the late XIX century, as different reasonable methods led to different conclusions. But as soon as the radioactive decay evidence became available, everyone was convinced of that.

How did the laws that govern matter and energy insult to the sacred dogma of the day? The laws of Newton and Maxwell did not insult anything, as far as I know.

I guess it could be said that Darwinian evolution insulted some sacred dogmas, but I am not sure Pinker is using that example. Darwin had no trouble publishing his books and papers, and in achieving high status in the scientific community.

Pinker seems to be influenced by Karl Popper's falsification theory, by Marxist idealization of revolutions, and by paradigm shift theory, where the Copernican revolution is by far the best example of a paradigm shift. But what "everyone knows" is not really true. The book by Copernicus was published with an official imprimatur of the Catholic Church. Later the Church said that nine sentences should be corrected.

Relativity teaches that motion is relative, and that it is valid to say that the Earth revolves around the Sun or that the Sun revolves around the Earth. Neither can be proved wrong. Paradigm shifters like Pinker like this example because it supposedly shows that scientific views are just opinions that will be overthrown when the dominant intellectuals lose power.

Some ancient Greeks figured out that the Sun was much bigger than the Earth, and so it made more sense to say that the Earth went around the Sun. Evidence was eventually found for Coriolis forces, showing that the Earth was not an inertial frame. Discovery of parallax showed that the Earth was moving relative to stars that are a few light-years away. But none of this is what the paradigm shifters focus on. They are preoccupied with reasoning that was available to Copernicus in 1543, which means simply deciding that one solar system model is true and another is false, for reasons other than physical or quantitative evidence.

This Popper/paradigm/Pinker view of science is insidious, as it portrays scientific truth as just opinion that happens to be fashionable. He acts as if he is defending science but he is really not, because he is denying that they discover lasting truths about the world.

And if you object to these arguments — if you want to expose a flaw in my logic or a lapse in my accuracy — it’s the right of free speech that allows you to do so.

I do think that it is important to criticize Pinker because he is somehow allowed to define science to the public as much as any other American professor. He is a big improvement over the late Stephen Jay Gould, but he gets away with sweeping and biased statements. His essay reads like what you might expect from some non-scientist who only took some watered-down science appreciation course in college.

4 comments:

How was Karl Popper wrong about the requirement of falsification? It actually is a requirement of physics experiments. You MUST be able to measure and test it, and the test must be falsifiable, otherwise, you are blowing hot air.

Pick up a physics book and look what it says about the scientific method in the first chapter. I have several Physics books lying about the place, would you like me to pull quotes from each of them confirming this? Are non scientists writing all the physics text books now? oh dear.

Better yet, please explain why falsification is unnecessary in scientific endeavors. I'm honestly curious to see why you think a prediction that can never be proven wrong no matter the result is part of science. This is the tripe that I hear from the Anthropogenic Global Warming camp all the time. They make a prediction, it's wrong, but no matter what, they continue to claim their theory is correct. Ask them to provide what would be required for their theory to be proven incorrect or falsified, they fall silent.

Predictions often get proved wrong, but that is not what Pinker is saying. He says that the "beloved convictions" are proved wrong. That is very rare.

Popper was not wrong about the requirement that theories be falsifiable. My problem with him that he was an anti-positivist. I will post some more about this. In the meantime, all I am saying here is that Popper and others influenced Pinker.

Popper proposed the falsifiability criterion not in order to highlight the fact that science is based on or progresses via the experimental method, but actually, to subtly undermine the very basis of science, viz., induction.

A great defence of induction, going beyond the Enlightenment times theory, is in a recent book by David Harriman: "Induction in Physics." For whatever my opinion is worth, I strongly recommend it for a permanent place on your book shelf. [Also, for reading it... :) ]

For the time being, just observe that Popper requires *theories* to be falsifiable, not *tests*.

A correct statement here is: For a theory to be valid, it must have objectively verifiable inductive bases, and objectively verifiable implications.

The implications don't have to take the form of true/false. They can also be just true/non-true. The term "verifiable implications" isn't necessarily the same as predictions, though the latter sure are included in the former.

Consider Newton's mechanics. He rightly regarded the three laws as axioms (though "postulates" is the form in which you are more likely to have read them described.) He also regarded his idea of the absolute space as an axiom. None of these are supposed to be open to "testing." They are open to a probing concerning their inductive bases---which is not the same thing as testing. However, the theory then makes some predictions concerning motions of objects, which are then open to testing---and which are falsifiable.

But therefore to describe this theory as falsifiable, is to pre-emptively throw out the very inductive bases of those axioms, their scope of reference, and therefore, the scope of their (and the theory's) applicability. As Roger rightly indicates, it is to pull down a difficult/great/towering inductive achievement down to the level of "opinons" if not subjective whims which, once their time runs out, will be "found out."

The last never happens with properly inductive theories. What is known as the (special) theory of relativity, does not "falsify" Newton's theory---it "merely" extends and subsumes the older theory, in the context that massive objects also carry charges. Remove the charge, and the "relativity" theory reduces to Newton's. Newtonian mechanics was not an opinion which would have to wither when a superior (more complex) opinion mysteriously descended from some supernaturally gifted elite.

It is also possible that a *new* theory does not extend an old theory but merely recasts it on some other conceptual basis: in some more easily understood concepts/framework that essentially carries the same factual content (or has the same scope) as an earlier established theory---to whatever extent the earlier theory was established. Such formulations also qualify for the title: "new theory." There are 9+ formulations of the mainstream QM, and each of them offers a certain cognitive advantage in certain respects. Thus, the "epistemological suitability to reduce the cognitive load in certain contexts" itself can also be a good goal for theory-building.